This happens to me in Adobe Illustrator CS3: Accordingly when I flip (turn upside down the pen to the eraser side) in Illustrator, the eraser is automatically supposed to be activated. Unfortunately this is not the case for me - the pen or whatever selected tool just keeps active. I have re-installed the latest tablet/pen drivers, restarted both the computer and program but the eraser still doesn't kick in when pen is flipped. However, the flipped pen to eraser does work in some other software like Adobe Photoshop Elements. Any and all help is appreciated.